1. Field of the Invention
This invention relates generally to novel poly-trisaryl-1,3,5-triazine carbamates and the use thereof to protect against actinic radiation.
2. Description of Related Art
Exposure to sunlight and other sources of ultraviolet radiation are known to cause degradation of a variety of materials, especially polymeric materials. For example, polymeric materials such as plastics often discolor and/or become brittle as a result of prolonged exposure to ultraviolet light. Accordingly, a large body of art has been developed directed towards materials such as ultraviolet light absorbers and stabilizers which are capable of inhibiting such degradation.
A class of materials known to be ultraviolet light absorbers are trisaryl-1,3,5-triazines, in which at least one of the aryl rings has a hydroxyl group ortho to the point of attachment to the triazine ring. In general this class of materials is well known in the art. Disclosures of a number of such trisaryl-1,3,5-triazines can be found in the following publications, all of which are incorporated by reference herein for all purposes as if fully set forth: U.S. Pat. Nos. 3,118,887, 3,242,175, 3,244,708, 3,249,608, 3,268,474, 3,843,371, 4,619,956, 4,740,542, 4,775,707 4,826,978, 4,962,142, 5,030,731, 5,071,981, 5,084,570, 5,106,891, 5,185,445, 5,189,084, 5,198,498, 5,288,778, 5,298,067, 5,322,868, 5,354,794, 5,369,140, 5,412,008, 5,420,204, 5,461,151 and 5,478,935; Canadian Patent Documents CA A1-2162645 and CA 2,032,669; UK Patent Documents GB1033387 and GB-A-2293823; Swiss Patent Documents CH480091 and CH484695; European Patent Documents EP-A-0434608, EP-A-0434619, EP-A-0444323, EP-A-0649841, EP-A-0654469, EP-A-0704437, EP-A-0706083; and PCT Patent Documents WO95/22959 and WO96/28431.
Typically, the aforementioned aryl ring with the hydroxyl group ortho to the point of attachment to the triazine ring is based on resorcinol and, consequently, this aryl ring also contains a second substituent (either a hydroxyl group or a derivative thereof) para- to the point of attachment to the triazine ring. This second substituent can be "non-reactive," as in the case of an alkyloxy group, or "reactive" as in the case of a hydroxyalkyloxy (active hydrogen reactive site) or (meth)acryloyl (ethylenic unsaturation reactive site) group. The former are typically referred to as "non-bondable" trisaryl-1,3,5-triazines, and the latter are referred to as "bondable" trisaryl-1,3,5-triazines.
Many polymer additives (such as ultraviolet light stabilizers) may suffer from a disadvantage that they volatilize or migrate out of the polymer substrate to be protected, or that they are absorbed (chemically or physically) by one or more systems components (such as pigments), thereby diminishing their effectiveness.
Although the presently claimed poly triazine carbamates are not bondable, it is believed that due to their high molecular weight, these triazines will exhibit higher permanence due to reduced volatility and reduced migration within the materials in which they are employed. In particular, it is believed that these triazines will exhibit greater thermal stability than other carbamate containing triazines formed directly from phenolic systems, particularly those in which the carbamate group is bonded directly to the aromatic ring.
EP 434,619 and CA 2,032,669 generically disclose various bondable phenolic carbamoyl triazines and the incorporation of these compounds into polymers by chemical bonding. Additionally, U.S. Pat. No. 5,354,794 discloses generically triazines with one or more carbonyl and/or ester groups. However, the inventors are unaware of any prior art which discloses the novel poly-trisaryl-1,3,5-triazine carbamates of the present invention.